Assertion : Materials are exchanged between epithelial and connective tissues by diffusion.
Reason : Blood vessels are usually absent in epithelial tissue

Options

A. If both assertion and reason are true and reason is the correct explanation of assertion.
B. If both assertion and reason are true but reason is not the correct explanation of assertion.
C. If assertion is true but reason is false.
D. If both assertion and reason are false.

Explanation

To solve the question, we need to analyze both the assertion and the reason provided.

### Step-by-Step Solution:

1. **Understanding the Assertion**:
- The assertion states that materials are exchanged between epithelial and connective tissues by diffusion.
- Epithelial tissues form a protective layer and are avascular (lack blood vessels), relying on diffusion for nutrient and waste exchange with the underlying connective tissue.

**Hint**: Think about how nutrients and waste products move between tissues that do not have direct blood supply.

2. **Understanding the Reason**:
- The reason states that blood vessels are usually absent in epithelial tissue.
- This is true; epithelial tissues do not contain blood vessels and instead receive nutrients and oxygen from the underlying connective tissue through the basement membrane.

**Hint**: Consider the structural characteristics of epithelial tissue and how they relate to their function.

3. **Evaluating the Relationship**:
- Both the assertion and reason are correct. However, the reason does not fully explain why diffusion occurs. The assertion is about the exchange process, while the reason merely states the absence of blood vessels without addressing the role of the basement membrane in facilitating diffusion.

**Hint**: Reflect on whether the reason directly supports the assertion or if it merely states a fact.

4. **Conclusion**:
- The assertion is correct, and the reason is also correct, but the reason does not adequately explain the assertion. Therefore, the correct answer is that both statements are true, but the reason is not the correct explanation for the assertion.

### Final Answer:
- The assertion is true, the reason is true, but the reason does not explain the assertion correctly.

### Answer Option:
- Option B: Both assertion and reason are true, but the reason is not the correct explanation for the assertion.

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